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A protector system that is applied at the beginning of the television technique, therefore most often found on old aircraft models. If the high voltage anode of the picture tube flyback tranfo exceed the permitted limit, the picture tube can generate x-rays from the anode and shadowmask are bombarded by electrons at high speed. To avoid this problem then mounted x-ray surge protector circuit , which automatically "horizontal section will be turned off" if the high voltage from the flyback over. X-Ray vertical protect The workings of x-ray protector: High voltage flyback sampled (generally taken from the pin-heater), rectified and is derived using a divider (devider) that uses a resistor-type high-precision resistor. Sample voltage is used to determine whether the condition is normal flyback voltage or over. A "zener diode" as a voltage sensor connected to the sample. In normal conditions the amount of the sample voltage is below the zener voltage of diode so that th...

Protect your expensive batteries from discharge damage with this mini-sized electronic cutout switch. It uses virtually no power and can be built to suit a wide range of battery voltages. Main Features Disconnects load at preset battery voltage Automatically reconnects load when battery recharged Ultra-low power consumption (<20ma) Miniature size 10A maximum rating Suitable for use with 4.8-12.5V batteries Transient voltage protection (optional) Suitable for use in... Cars, boats & caravans Security systems Emergency lighting Small solar installations Camera battery packs Many other low-power applications Picture of the project: Back in May 2002, we (Silicon Chip) presented the "Battery Guardian", a project designed specifically for protecting 12V car batteries from over-discharge. This unit has proven to be very popular and is still available from kit suppliers. This new design does not supersede the Battery Guardian – at least not when it comes to 12V car batteries....

Many of our costly appliances require three-phase AC supply for operation. Failure of any of the phases makes the appliance prone to erratic functioning and may even lead to failure. Hence it is of paramount importance to monitor the availability of the three-phase supply and switch off the appliance in the event of failure of one or two phases. The power to the appliance should resume with the availability of all phases of the supply with certain time delay in order to avoid surges and momentary fluctuations. The complete circuit of a threephase appliance protector is described here. It requires three-phase supply, three 12V relays and a timer IC NE555 along with 230V coil contactor having four poles. Relays RL1 and RL2 act as a sensing devices for phases Y and B, respectively. These relays are connected such that each acts as an enabling device for the subsequent relay. Therefore the combination of the relays forms a logical AND gate connected serially. The availability of phase R en...